He crossed the Danube on his cloak ...

"Legend has it that he was the son of a king, from Dacia or Denmark, who married a French princess in Paris. During the wedding night, the story goes, he was afflicted with a sense of profound unworthiness. Today, he is supposed to have said to his bride, our bodies are adorned, but tomorrow they will be food for worms. Before the break of day, he fled, making a pilgrimage to Italy, where he lived in solitude until he felt the power to work miracles arising within him [...] and went over the Alps to Germany. At Regensburg he crossed the Danube on his cloak, and there made a broken glass whole again; and, in the house of a wheelwright too mean to spare the kindling, lit a fire with icicles. This story of the burning of the frozen substance of life has, of late, meant much to me, and I wonder now whether inner coldness and desolation may not be the precondition for making the world believe, by a kind of fraudulent showmanship, that one's own wretched heart is still aglow." -- W. G. Sebald, The Rings of Saturn